The Duchess of Cambridge, Kate Middleton, reportedly went into labor early Monday morning with sources confirming she was admitted to St, Mary's Hospital in London.

Middleton, 31, reportedly went into labor naturally and is said to be in good condition as the world awaits the birth of her and Prince William's first child.

"Her Royal Highness The Duchess of Cambridge has been admitted to St. Mary's Hospital, Paddington, London in the early stages of labor," Clarence House tweeted July 22. "The Duchess traveled by car from Kensington Palace to the Lindo Wing at St. Mary's Hospital with The Duke of Cambridge."

William, 30, is believed to be waiting anxiously at the hospital with a source revealing that Middleton's labor is "progressing well," according to Daily Mail UK.

Royal officials are expected to use a wood and gold easel, on which a framed announcement will be placed, to confirm the birth of Middleton and William's baby. The frame, which was used to confirm the birth of William in 1982, will reportedly be placed behind the gates of Buckingham Palace.

The couple's baby will become third in the line to the throne, ultimately displacing William's younger brother, Prince Harry, who will become fourth in-line to succession.

As Middleton went into labor, Queen Elizabeth II received the news while in Windsor Castle while Prince Charles was told while in York.

The Queen expressed her anxiousness for the royal birth on Wednesday particularly because she is preparing to go on vacation in coming days.

"I would very much like [the baby] to arrive because I'm going on holiday soon ... I wish it would hurry up," the Queen said during a trip to Lake Windermere in Cumbria.

While St. James's palace previously confirmed that the Duke and Duchess do not know the gender of their unborn baby, Middleton's uncle, Gary Goldsmith, suspects otherwise.

"My suspicion is that they're having a baby girl. But, of course, I don't know that for fact. I believe Kate and William have kept the sex of their child a secret to everyone but themselves," Goldsmith told The Daily Mirror.

"It would be brilliant, wouldn't it, if they do have a little girl? To have one of my family, my niece, making history will be absolutely unbelievable," he added.